Saturday, April 2, 2011


1. About me
An excellent student will show a real passion for science and be able to present their ideas with confidence, clarity and enthusiasm, and explain what winning would mean to them.

My name is Wong Pui Choo. I am 14 this year. I am currently studying at Peirce Secondary School. I am strong in math and mother tongue as compared to other subject. I am strong in mother tongue might because I started writing chinese character at a very young age. And during conversation with friends and family members chinese is mostly use. My hobbies are reading books and listening to music. The type of book I like to read are mystery book, story related to crime and inspiration book. I also like playing sports as it keeps me active and healthy. I like running, playing basketball and badminton the most.

My name is Farina Bte Satiman. I am turning fourteen this year. My birthday falls on the third of may. I was born in Easrshore Hospital. I lived in a family of four which consists of my mother, my grandmother, my grandfather and myself. I am currently staying in Ang Mo Kio Blk 335 Ave 1 #02-2007. I lived in a four room flat, nearby a swimming complex and Bishan Park. I am a single child and do not have any siblings. I am currently studying in Peirce Secondary School and my CCA is St John Ambulance Brigade. My previous school was Marymount the convent school. Things I like to do are playing sports and outdoor activities as I am more of an outdoor person. Lastly I would like to talk about my friends in school. Even though its only have been a year and three months, I think I made more than a hundred friends.

My name is Nur Afiah Hashim. I am 14 this year and I study in Peirce Secondary School. I am the oldest of four children. The closest I have to older siblings would be my seniors and my cousins. I like listening to songs, writing, reading and doing sports. I love badminton but I do netball as I do not have badminton as a choice of CCA. I aspire to be either a psychologist or lawyer. I would like to be psychologist because I want to understand people more and help them. I also want to be a lawyer because I want to help the innocent people and fight for their right. I enjoy studying History and Math.

2. The Question
An excellent question will be interesting, creative, worded scientifically and relevant to the world today.

Can bleach remove all kinds of stains and why is it dangerous?

3. Hypothesis
An excellent hypothesis will lead on from the question, be tightly focused and build on existing knowledge.

We think that bleach will remove any kind of stain and even make the material much whiter.

4. Research
Excellent students will undertake research to help them shape their question and hypothesis and to put their work into a relevant, real-world context.

Different stains are removed using different solvents. What solvent to use depends on the agent that is causing the stain, and the material that has been stained. Bleaching powder is made up of mixture of calcium hypochlorite and the basic chloride with some slaked lime. It helps to whiten clothing and remove certain stains.
It is quite dangerous as bleaching powder contains calcium hypochlorite that will undergo self-heating and rapid decomposition accompanied by the release of toxin chlorine gas when it was not kept in a cool dry place away from any organic material.

5. Experiment
Excellent students will demonstrate that they have used good experimental techniques and describe their experiment clearly and in detail.

6. Data
Excellent data will be relevant, sufficient to support a conclusion and should be recorded accurately and precisely, and be presented clearly.

Clear results that have been tried about twice each.

7. Observations
Excellent observations will describe patterns or trends supported by the data.

Based on the experiments that we have done, we can conclude that bleach does not remove all kinds of stain and is not always as strong as we think it is.

8. Conclusion
An excellent conclusion will explain how the experiment answers the question or why it fails to do so and whether or not it supports the hypothesis.

After dipping the stain into the bleach solution and leaving it for 5 minutes, the stain does not disappear. Therefore, bleach does not remove all kinds of stains.